Dachshund Health.
As with any breed, there are some health conditions that Dachshund are more susceptible to, that owners need to be aware of to enable them to provide the best care for their dog.
Intervertebral Disc Disease (IVDD).
Intervertebral Disc Disease is the most common spinal disease in dogs, which is an age-related degenerative condition of the spine. All dogs’ discs degenerate over time, lose water, become more fibrous and sometimes mineralised. However, the condition is more common in chondrodystrophic breeds such as Dachshunds. For this reason, Dachshunds are more likely to suffer intervertebral disc problems at a much younger age than other breeds.
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Intervertebral discs are the fibrocartilaginous cushions between the vertebrae except for the first two cervical vertebrae, that allow movement, and are supportive shock absorbers. They consist of a fibrous outer rim, the annulus fibrosis, and a jelly like centre, the nucleus pulpous. When the intervertebral discs of chondrodystrophic breeds degenerate, they can calcify making the discs visible on radiographs.
Intervertebral disc degeneration results in diminished shock absorbing capacity and can lead to disc herniation and spinal cord compression. There are two types of disc herniation, and they are described as Hansen type I (nucleus pulpous degeneration and extrusion) and Hansen type II (annulus fibrosis degeneration and protrusion).
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Hansen type I is described as extrusion or herniation of the intervertebral disc and the structure of the disc can be described as comparable to a jam doughnut. An unaffected disc is compressible and squidgy, and they allow the vertebral column to flex, extend and twist. In a diseased disc the jam (the nucleus pulpous) becomes hard, and it can no longer compress. As a result, normal movement puts significant strain on the disc and eventually the doughnut tears and the jam explodes or oozes out in an upwards direction and can impacts and compresses the spinal cord. The velocity of the of the impact affects the severity of the injury as does the volume of disc extrusion. Type I disease is most common in small breeds of dogs (specifically chondrodystrophic breeds such as the Dachshund) aged two and above, although it can affect larger breeds as well. The clinical signs are pain and paralysis, in severe cases this is an emergency, and the patient should see a vet promptly. The onset is acute of clinical signs with the signs being variable however, this does not affect the prognosis.
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Hansen type II can be described similarly to human disc disease which occurs in those dogs without disproportionately short limbs (non-chondrodystrophic).
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Hansen type III disc disease which is also known as acute non-compressive or high-velocity low volume disc disease has an acute onset which occurs typically with heavy exercise or trauma. The normal nucleus explodes from a sudden tear in the annulus, and the injury to the spinal cord does not result in ongoing spinal cord compression. Dogs tend recover well with rehabilitation and physiotherapy and do not tend to require surgery.
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The main clinical sign is pain however, the patient may have difficulty in walking with poor control of the hindlimbs or paralysis. In severe cases the patient may develop myelomalacia which is softening and dying or the spinal cord, this ascends the spinal cord, and this can be fatal as it affects the nerves involved in breathing resulting in respiratory arrest. As previously mentioned, the main sign associated with intervertebral disc disease is pain in the back or neck. Disease in the lower back can be seen as hindlimb weakness, paralysis and urinary incontinence whereas disease in the neck can cause weakness to all four limbs. Aside from vocalisation the most common signs or spinal pain can be abnormal posture, shivering, panting, not wanting to move, difficulty jumping, difficulty going up and down the stairs, difficulty walking with poor control of the hindlimbs, paralysed bladder which causes difficulty in urinating, paralysis, complete loss of bladder function, and an inability to feel painful sensations.
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Intervertebral disc disease is diagnosed using radiographs, CT, and MRI scans, where the images reveal changes in the discs. The patient must lie completely still so this procedure is undertaken under general anaesthetic. Some dogs will require surgery and there are two types of surgery available Fenestration and decompressive.
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Fenestration is the simplest type of surgery whereby the nuclei pulpous are removed through a small window created in the annulus fibrosis to limit further disc extrusions. Any material in the vertebral canal is not removed, and if patient has severe spinal cord compression the neurological recovery will be prolonged and there may be neurological deficits. This type of surgery may or may not be done alongside decompressive surgery.
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Decompressive surgery is whereby the extruded disc material is removed from the spinal canal, this type of surgery is more difficult and requires specialised equipment. The type of surgery will depend on the site of the problem for example, the neck, the thoracolumbar, or the lumbosacral region. After surgery, a rehabilitation programme which included physiotherapy will be implemented alongside pain management.
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In some cases, dogs will not require surgery and can recover via conservative management however, this will usually be limited to those patients with pain only or mild symptoms. There may also be some success with the severe cases however, those dogs who have lost pain sensation are unlikely to respond to conservative management, and there is also a higher chance of another at some point in the patient’s life. Conservative management does avoid surgery and the main part of the management is to restrict movement whether this be a crate or a pen to avoid further extrusion alongside pain relief.
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Recovery with surgery and conservative management varies from case to case whereby some dogs recover quickly and there are some that do not recover well at all leaving them unable to walk again. For those that are unable to walk there is an option for mobility carts, which must be of an appropriate size for the dog and fitted correctly. Some dogs will have a requirement to have their bladder expressed if they are unable to urinate themselves which is a simple task to learn.
Progressive Retinal Atrophy – PRA Cord 1.
The Cord 1 PRA (Cone-rod dystrophy 1) is an inherited disease of the eye that occurs in the English Springer Spaniel, Miniature Long-Haired Dachshunds and Smooth-Haired Dachshunds.
The retina is a thin layer of neural cells that lines the back of the eyeball. The vertebrate retina contains photoreceptor cells (rods and cones) that respond to light. The cones mediate high-resolution vision and colour vision. The rods mediate lower-resolution, black-and-white, and night vision.
The degeneration of the retina results in loss of vision, often leading to blindness. There is currently no treatment for the disease. In contrast to rod-cone dystrophies, where firstly, the rod cells are affected and secondly, degeneration of the cone cells results in complete blindness of the dog, cone-rod dystrophies are characterised by the relatively early loss of cone photoreceptors.
The earliest ophthalmoscopic signs could appear at approximately 6 months of age but some dogs with the mutation are not diagnosed until much later in life, so owners may never see behavioural changes and never recognise that the dog can pass the mutation onto its offspring.
Since the diagnosis of retinal diseases in dogs may prove difficult, the genetic test on Cord 1 PRA helps to diagnose a specific form of disease and is also a useful tool for breeders to eliminate the mutated gene from the dog population.
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Trait of Inheritance:
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Cord 1 PRA is inherited as an autosomal recessive trait, and there are three conditions a dog can be: it can be clear (genotype N/N or homozygous normal) meaning that it does not carry the mutation and will not develop the cord 1 form of PRA. It also cannot pass the mutation onto its offspring it can be mated to another dog.
A dog which has one copy of the gene with the mutation and one copy without the mutation is called a carrier of heterozygous (genotype N/PRA); whilst it will not be affected by cord 1 PRA it can pass the mutation onto its offspring and should therefore only be mated to clear dogs.
Dogs that develop this form of PRA have two gene copies with the mutation (genotype PRA/PRA or homozygous affected); they will always pass the mutated gene onto their offspring and should also be mated only to clear dogs.​​
